inchworm

From inch +‎ worm. So called because their gradual movement seems to be measuring the ground; compare measuring worm.

• (UK) IPA^(key): /ˈɪnt͡ʃ.wɜːm/
• (US) IPA^(key): /ˈɪnt͡ʃ.wɚm/

inchworm (plural inchworms)

1. The larva of a moth of the family Geometridae.

inchworm (third-person singular simple present inchworms, present participle inchworming, simple past and past participle inchwormed)

1. (informal, idiomatic, intransitive) To move in a looping fashion, like an inchworm.
2. (informal, idiomatic, intransitive) To crawl or creep slowly.

• (larva): geometrid, looper, measuring worm, spanworm